Adhesive films are often used to protect carpeting and other floor finishes. There is a continuing need for a dispenser to make application of the film faster and easier. The most common roll widths are 24 inches, 30 inches, 36 inches, and 48 inches. Some manufacturers offer a dispenser that accommodates each roll width and others offer a dispenser that accommodates several different widths.
FIG. 1 shows a prior art device 10 that can accommodate several widths of film roll 12. Device 10 has a central support assembly 14, a right support assembly 36, a left support assembly 44, a film pressing tube 52, and a handle 54. Right support assembly 36 has a bracket 38, a film mounting roller 40 adapted to receive one end of film roll 12, and a film pressing roller 42 adapted to receive one end of film pressing tube 52. Left support assembly 44 has a bracket 46, a film mounting roller 48 adapted to receive the opposite end of film roll 12, and a film pressing roller 50 adapted to receive the opposite end of film pressing tube 52. Central support assembly 14 employs an elongated member 16 having a hollow cavity 18 and open end portions 20 and 22. To accommodate several widths of film, central support assembly 14 has first and second extension members 24 and 30. First extension member 24 has an end portion 26 telescopically mounted within hollow cavity 19 thru end portion 20 of elongated member 16 and an end portion 28 welded to bracket 38 of right support assembly 36. Second extension member 30 has an end portion 32 telescopically mounted within hollow cavity 18 thru end portion 22 of elongated member 16 and an end portion 34 welded to bracket 46 of left support assembly 44. One significant problem with device 10 is that it cannot double its width and cannot fit all of the most common film roll widths, namely, 24 inches, 30 inches, 36 inches, and 48 inches.
FIG. 2 shows a prior art device 56 that accommodates film rolls of 24 inches, 30 inches, 36 inches, and 48 inches. Device 56 has a single-cavity elongated member or housing 58 with consecutively smaller extension members or tubes 60 and 62 telescoping from the same side of elongated member 58. One significant problem with device 56 is that handle 54 is not always centered on the dispenser at widths greater than 24 inches thereby making it difficult to control the unit.
Another problem common to devices 10 and 56 lies in the difficulty with loading both film roll 12 and film pressing tube 52 onto the dispenser. FIG. 3 is an exploded view of device 10 showing film mounting rollers 40 and 48, and film pressing rollers 42 and 50. The depth or length of film mounting roller 40 and film pressing roller 42 (and rollers 48 and 50) are approximately the same. Because both rollers 40 and 42 have the same depth or length, the user must maneuver both film roll 12 and film pressing tube 52 into position, while at the same time telescoping the dispenser to the closed position. This creates a clumsy operation for a person working alone, especially with large heavy rolls of film. Quite often the pressing film tube falls off while the person is mounting the film roll.
FIG. 4 shows a set of prior art film pressing rollers 64. In conventional devices, each film width of 24 inches, 30 inches, 36 inches, and 48 inches employs a matching or corresponding film pressing roller 66, 68, 70, and 72.